How do you discipline a child who just doesn't care?

Ok, here's the deal. My child is pretty much well behaved MOST of the time. I don't have anything worthy of super nanny like yelling, fighting, kicking etc. His behavior is more of a manipulation mind game. I have constant power struggles with him. He doesn't listen at all. But they thing is half the time he is SO SNEAKY about it. For instance if I say it's time to go to get in his pj's and go to bed he might just go to bed in his clothes. Or the other day I was very sick and I told him he needed to get help with his homework from my friend that was over helping me with him and he didn't do it and instead wrote a bunch of gibberish on his homework sheet. And he will do things like pretend he can't read or write when he has been doing those things since preschool and now he is in the 1st grade. And when he does do something really bad, I can't seem to find a suitable punishment at all! You name it, I've tried it. Time-outs, taking away toys/privileges, behavior charts, rewards, grounding etc. Once we got to a point where we took away every single thing in his room including all his brand new birthday presents and even the curtains (we only left the bed sheets) and he still didn't care. He just sat in his room, content as can be. I can't think of a single punishment I haven't tried. HELP!